Table 1.
Descriptive statistics for demographic and baseline physiological variables.
| Full sample |
AAs |
EAs |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| M | SD | M | SD | M | SD | p | mDiff | Lower | Upper | |
| Gender | 54 (76) | 33 (21) | 21 (52) | 0.01 | ||||||
| Age | 19.68 | 1.96 | 19.61 | 1.92 | 19.74 | 1.99 | 0.70 | 0.14 | −0.55 | 0.82 |
| BMI | 25.52 | 4.93 | 26.75 | 5.83 | 24.59 | 3.92 | 0.01 | −2.16 | −3.85 | −0.47 |
| Activity | 4.25 | 2.15 | 3.81 | 2.36 | 4.57 | 1.93 | 0.08 | 0.75 | 0.00 | 1.51 |
| HRV | 54.86 | 25.89 | 61.41 | 28.17 | 49.90 | 23.00 | 0.01 | −11.51 | −20.40 | −2.63 |
| HR | 73.44 | 10.88 | 72.63 | 9.74 | 74.06 | 11.70 | 0.46 | 1.42 | −2.40 | 5.24 |
| MAP | 81.99 | 12.87 | 81.71 | 12.47 | 81.58 | 12.82 | 0.96 | −0.13 | −4.72 | 4.47 |
| SBP | 119.50 | 16.54 | 118.50 | 15.21 | 120.43 | 16.99 | 0.52 | 1.93 | −3.96 | 7.82 |
| DBP | 64.05 | 11.74 | 63.57 | 11.17 | 63.81 | 11.63 | 0.91 | 0.24 | −3.91 | 4.39 |
| TPR | 0.83 | 0.28 | 0.85 | 0.29 | 0.83 | 0.28 | 0.74 | −0.02 | −0.12 | 0.09 |
| CO | 6.25 | 1.47 | 6.20 | 1.53 | 6.31 | 1.44 | 0.71 | 0.10 | −0.44 | 0.64 |
| SV | 84.91 | 20.38 | 85.11 | 23.23 | 84.42 | 17.63 | 0.10 | −0.69 | −8.04 | 6.66 |
| SBPv | 4.22 | 2.09 | 3.88 | 1.27 | 4.49 | 2.53 | 0.10 | 0.61 | −0.12 | 1.34 |
| TPRv | 59.29 | 38.23 | 62.21 | 36.60 | 57.06 | 39.53 | 0.45 | −5.15 | −18.61 | 8.31 |
| cBRS | 16.84 | 8.82 | 18.94 | 10.58 | 15.26 | 6.88 | 0.02 | −3.68 | −6.72 | −0.65 |
| cBEI | 63.77 | 11.79 | 64.10 | 13.26 | 63.52 | 10.63 | 0.78 | −0.58 | −4.72 | 3.57 |
| vBRS | 16.03 | 12.56 | 17.27 | 15.25 | 15.08 | 10.04 | 0.33 | 2.18 | −2.24 | 6.60 |
| vBEI | 34.12 | 10.33 | 31.20 | 10.13 | 36.35 | 9.98 | 0.00 | 5.15 | 1.62 | 8.68 |
| mBRS | 1.78 | 0.83 | 1.98 | 0.91 | 1.62 | 0.74 | 0.01 | 0.37 | 0.08 | 0.65 |
| mBEI | 36.43 | 15.22 | 35.70 | 16.69 | 36.98 | 14.09 | 0.64 | 1.27 | −4.07 | 6.62 |
Note. This table provides means and standard deviations for all variables of interest for the full sample and stratified by African Americans (AAs) and European Americans (EAs), with associated t-test significance values and upper and lower confidence intervals (noted as upper and lower, respectively). Chi-squared tests were used to determine group differences in gender (represented in this table as count, men in brackets). Age in years; body mass index (BMI); Houston Non-Exercise Inventory (Activity); heart rate variability (HRV; ms), heart rate (HR; beats per minute); systolic blood pressure (SBP; mmHg); diastolic blood pressure (DBP; mmHg); total peripheral resistance (TPR; mmHg.s/ml); cardiac output (CO; l/min); stroke volume (SV; l/min); systolic blood pressure variability (SBPv); total peripheral resistance variability (TPRv) baroreflex sensitivity (BRS; ms) and baroreflex effectiveness (BEI; %). Limbs are denoted as: c = cardiac, v = vascular, m = myocardial. Bolded lines denote significant differences.
In the present study, data were available for 130 individuals between the ages of 18 and 30 (54 women, mean age of 19.7 years, standard deviation of 2 years). Of the 130 subjects, there were 57 AAs (33 females, mean age of 19.7 years) and 73 EAs (21 females, mean age of 19.6 years).